Recently, a plasma display apparatus has received attention as a display panel having good visibility or a thin display device, and have been developed for high resolution and larger screen.
Plasma display apparatuses are classified into two driving systems, i.e., an AC type and a DC type, and classified into two electric discharge systems, i.e., a surface discharge type and an opposed discharge type. The AC and surface discharge type plasma display apparatus has become mainstream, because of high resolution, a large display and easy manufacturing.
FIG. 8 shows an example of the plasma display apparatus. As shown in FIG. 8, a casing for accommodating panel 1 is formed of front frame 2 and metal back cover 3. Front cover 4 made of glass and the like, which is used as an optical filter or a protector, is disposed on an opening of front frame 2. Silver is deposited on front cover 4 for suppressing unwanted radiation of electromagnetic waves. A plurality of venting holes 5 for venting heat, which is generated from panel 1, are formed on back cover 3. Panel 1 adheres to chassis (sustaining board) 6 via heat conducting sheet 7, where chassis 6 made of aluminum and the like is used as a sustaining board and a radiating board. Heat conducting sheet 7 is made of a double-sided adhesive sheet, e.g., acrylic, urethane or silicon, or has adhesive layers on both sides. A plurality of circuit blocks 8, which drive panel 1 for display, are disposed at a rear surface of chassis 6. Heat conducting sheet 7 has a function of transmitting heat generated from panel 1 to chassis 6 efficiently, and chassis 6 having a function of a radiating board radiates the heat. Circuit blocks 8 include electric circuits for driving and controlling panel 1 for display, and are connected electrically with lead-wires of electrodes routed at margins of panel 1, by using a plurality of flexible wiring boards (not shown), which extend over four margins of chassis 6.
Bosses 9, which are produced in one piece by die-casting or are produced by fixing pins, protrude from a rear surface of chassis 6 and are used for setting circuit blocks 8 or fixing back cover 3.
In the plasma display apparatus discussed above, panel 1 is required to be bonded entirely to chassis 6 so as to not separate from each other while being transported or operated, and so as to transmit transmitting heat generated from panel 1 to chassis 6 efficiently.
The conventional process of bonding panel 1 to chassis (sustaining board) 6 via heat conducting sheet 7 including an adhesive layer is performed by handwork for preventing panel 1 from breaking, because panel 1 is made of glass. As a result, a bonding area between heat conducting sheet 7 and panel 1 or chassis 6 becomes small, and unevenness of bonding tends to appear on panel 1. In other words, panel 1 does not adhere to chassis 6 firmly, so that heat generated from panel 1 can not be transmitted to chassis 6 efficiently. Moreover, mechanical strength of the plasma display apparatus decreases, because panel 1 and chassis 6 are not integrated.
The present invention addresses the problems discussed above, and aims to provide a plasma display apparatus which has efficient radiating-heat characteristics and high strength by securing a sufficient bonding area between a panel and a sustaining board.